Update specs/jsonschema-core.md

Co-authored-by: Jason Desrosiers <[email protected]>

Author: gregsdennis

specs/jsonschema-core.md

@@ -1992,7 +1992,9 @@ action based on `$comment` contents.
 
 When encountering an IRI that also represents a valid file system or network
 location, implementations are discouraged from automatically making an operation to
-access that location. Schema authors should take care when configuring
+access that location. Implementations that choose to support retrieval over untrusted
+connections should require users to configure the implementation to enable that 
+functionality.
 implementations to operate over a file system or network as this could expose
 the host system.